//package com.scr.apigateway;
//import com.scr.apiclientsdk.utils.SignUtils;
//import lombok.extern.slf4j.Slf4j;
//import org.apache.dubbo.config.annotation.DubboReference;
//import org.reactivestreams.Publisher;
//import org.springframework.cloud.gateway.filter.GatewayFilterChain;
//import org.springframework.cloud.gateway.filter.GlobalFilter;
//import org.springframework.core.Ordered;
//import org.springframework.core.io.buffer.DataBuffer;
//import org.springframework.core.io.buffer.DataBufferFactory;
//import org.springframework.core.io.buffer.DataBufferUtils;
//import org.springframework.http.HttpHeaders;
//import org.springframework.http.HttpMethod;
//import org.springframework.http.HttpStatus;
//import org.springframework.http.server.reactive.ServerHttpRequest;
//import org.springframework.http.server.reactive.ServerHttpResponse;
//import org.springframework.http.server.reactive.ServerHttpResponseDecorator;
//import org.springframework.stereotype.Component;
//import org.springframework.web.server.ServerWebExchange;
//import reactor.core.publisher.Flux;
//import reactor.core.publisher.Mono;
//import com.scr.apiclientsdk.model.User;
//import java.nio.charset.StandardCharsets;
//import java.util.ArrayList;
//import java.util.Arrays;
//import java.util.List;
//
///**
// * 全局过滤
// */
//@Slf4j
//@Component
//public class CustomGlobalFilter implements GlobalFilter, Ordered {
//
//    private static final List<String> IP_WHITE_LIST = Arrays.asList("127.0.0.1");
//
//    private static final String INTERFACE_HOST = "http://localhost:8123";
//
//    @DubboReference
//    private InnerUserService innerUserService;
//
//    @DubboReference
//    private InnerInterfaceInfoService innerInterfaceInfoService;
//
//    @DubboReference
//    private InnerUserInterfaceInfoService innerUserInterfaceInfoService;
//
//    @Override
//    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
//        // 1. 请求日志
//        ServerHttpRequest request = exchange.getRequest();
//        String path = INTERFACE_HOST + request.getPath().value();
//        String method = request.getMethod().toString();
//        log.info("请求唯一标识：" + request.getId());
//        log.info("请求路径：" + path);
//        log.info("请求方法：" + method);
//        log.info("请求参数：" + request.getQueryParams());
//        String sourceAddress = request.getLocalAddress().getHostString();
//        log.info("请求来源地址：" + sourceAddress);
//        log.info("请求来源地址：" + request.getRemoteAddress());
//        ServerHttpResponse response = exchange.getResponse();
//        // 2. 访问控制 - 黑白名单
//        if (!IP_WHITE_LIST.contains(sourceAddress)) {
//            response.setStatusCode(HttpStatus.FORBIDDEN);
//            return response.setComplete();
//        }
//        // 3. 用户鉴权（判断 ak、sk 是否合法）
//        HttpHeaders headers = request.getHeaders();
//        String accessKey = headers.getFirst("accessKey");
//        String nonce = headers.getFirst("nonce");
//        String timestamp = headers.getFirst("timestamp");
//        String sign = headers.getFirst("sign");
//        String body = headers.getFirst("body");
//        // todo 实际情况应该是去数据库中查是否已分配给用户
//        User invokeUser = null;
//        try {
//            invokeUser = innerUserService.getInvokeUser(accessKey);
//        } catch (Exception e) {
//            log.error("getInvokeUser error", e);
//        }
//        if (invokeUser == null) {
//            return handleNoAuth(response);
//        }
//        if (Long.parseLong(nonce) > 10000L) {
//            return handleNoAuth(response);
//        }
//        // 时间和当前时间不能超过 5 分钟
//        Long currentTime = System.currentTimeMillis() / 1000;
//        final Long FIVE_MINUTES = 60 * 5L;
//        if ((currentTime - Long.parseLong(timestamp)) >= FIVE_MINUTES) {
//            return handleNoAuth(response);
//        }
////        // 实际情况中是从数据库中查出 secretKey
////        String secretKey = invokeUser.getSecretKey();
//        String serverSign = SignUtils.genSign(body, "abcdefgh");
//        if (sign == null || !sign.equals(serverSign)) {
//            return handleNoAuth(response);
//        }
////        // 4. 请求的模拟接口是否存在，以及请求方法是否匹配
////        InterfaceInfo interfaceInfo = null;
////        try {
////            interfaceInfo = innerInterfaceInfoService.getInterfaceInfo(path, method);
////        } catch (Exception e) {
////            log.error("getInterfaceInfo error", e);
////        }
////        if (interfaceInfo == null) {
////            return handleNoAuth(response);
////        }
//        // todo 是否还有调用次数
//        // 5. 请求转发，调用模拟接口 + 响应日志
//        //        Mono<Void> filter = chain.filter(exchange);
//        //        return filter;
////        return handleResponse(exchange, chain, interfaceInfo.getId(), invokeUser.getId());
//        return response.setComplete();
//    }
//
//    /**
//     * 处理响应
//     *
//     * @param exchange
//     * @param chain
//     * @return
//     */
//    public Mono<Void> handleResponse(ServerWebExchange exchange, GatewayFilterChain chain, long interfaceInfoId, long userId) {
//        try {
//            ServerHttpResponse originalResponse = exchange.getResponse();
//            // 缓存数据的工厂
//            DataBufferFactory bufferFactory = originalResponse.bufferFactory();
//            // 拿到响应码
//            HttpStatus statusCode = originalResponse.getStatusCode();
//            if (statusCode == HttpStatus.OK) {
//                // 装饰，增强能力
//                ServerHttpResponseDecorator decoratedResponse = new ServerHttpResponseDecorator(originalResponse) {
//                    // 等调用完转发的接口后才会执行
//                    @Override
//                    public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
//                        log.info("body instanceof Flux: {}", (body instanceof Flux));
//                        if (body instanceof Flux) {
//                            Flux<? extends DataBuffer> fluxBody = Flux.from(body);
//                            // 往返回值里写数据
//                            // 拼接字符串
//                            return super.writeWith(
//                                    fluxBody.map(dataBuffer -> {
//                                        // 7. 调用成功，接口调用次数 + 1 invokeCount
//                                        try {
//                                            innerUserInterfaceInfoService.invokeCount(interfaceInfoId, userId);
//                                        } catch (Exception e) {
//                                            log.error("invokeCount error", e);
//                                        }
//                                        byte[] content = new byte[dataBuffer.readableByteCount()];
//                                        dataBuffer.read(content);
//                                        DataBufferUtils.release(dataBuffer);//释放掉内存
//                                        // 构建日志
//                                        StringBuilder sb2 = new StringBuilder(200);
//                                        List<Object> rspArgs = new ArrayList<>();
//                                        rspArgs.add(originalResponse.getStatusCode());
//                                        String data = new String(content, StandardCharsets.UTF_8); //data
//                                        sb2.append(data);
//                                        // 打印日志
//                                        log.info("响应结果：" + data);
//                                        return bufferFactory.wrap(content);
//                                    }));
//                        } else {
//                            // 8. 调用失败，返回一个规范的错误码
//                            log.error("<--- {} 响应code异常", getStatusCode());
//                        }
//                        return super.writeWith(body);
//                    }
//                };
//                // 设置 response 对象为装饰过的
//                return chain.filter(exchange.mutate().response(decoratedResponse).build());
//            }
//            return chain.filter(exchange); // 降级处理返回数据
//        } catch (Exception e) {
//            log.error("网关处理响应异常" + e);
//            return chain.filter(exchange);
//        }
//    }
//
//    @Override
//    public int getOrder() {
//        return -1;
//    }
//
//    public Mono<Void> handleNoAuth(ServerHttpResponse response) {
//        response.setStatusCode(HttpStatus.FORBIDDEN);
//        return response.setComplete();
//    }
//
//    public Mono<Void> handleInvokeError(ServerHttpResponse response) {
//        response.setStatusCode(HttpStatus.INTERNAL_SERVER_ERROR);
//        return response.setComplete();
//    }
//}